Creatine: a science‑backed complete guide

Creatine monohydrate is one of the most studied, proven supplements to improve strength, power, training volume, and lean mass. Used properly, it is safe, affordable, and effective.

TL;DR

• Best form: creatine monohydrate (micronized if you have GI sensitivity).
• Standard dose: 3–5 g per day, every day, at the same time.
• Loading (optional): 20 g/day for 5–7 days (4 × 5 g), then 3–5 g/day maintenance.
• Evidence‑based benefits: strength, power, speed, training volume, recovery, small increases in lean mass; potential cognitive benefits (working memory, mental fatigue resistance), extra value in vegans/older adults.
• Safety: excellent in healthy individuals at recommended doses; ensure adequate hydration. Seek medical advice if you have kidney disease, take medications, are pregnant/breastfeeding, or are underage.

What is creatine?

Creatine is a compound naturally present in the body (muscles, brain), synthesized from arginine, glycine, and methionine. It is stored mostly as phosphocreatine (PCr), an energy buffer that rapidly regenerates ATP — the cellular energy currency — during short, intense efforts.

Dietary sources: mainly meat and fish. Vegetarian/vegan diets provide little creatine, which is why supplementation often yields larger benefits in these groups.

How does it work? (mechanisms)

By increasing phosphocreatine stores in muscle (and possibly in the brain), creatine allows:

• Faster ATP resynthesis during explosive efforts (short sets, sprints, jumps).
• Higher training volume (more reps/loads at the same RPE).
• Better recovery between repeated bouts.

Over weeks, this translates to greater strength and muscle gains, largely because you can perform slightly more quality work each session.

Proven benefits

Performance and body composition

• ↑ Max strength and power (1RM, sprints, jumps) across several meta‑analyses.
• ↑ Reps possible at a given load; ↓ perceived exertion at equal volume.
• ↑ Lean mass (modest), especially in beginners, vegans, or low baseline stores.

Brain and cognition

• Promising effects on working memory, mental fatigue resistance, and cognitive performance under sleep deprivation or heat stress. Effects are more visible in people with low baseline intake (vegetarians/vegans) and older adults.

Health and special populations

• Older adults: supports strength/function (sarcopenia) particularly with resistance training.
• Vegetarians/vegans: often larger gains (lower baseline stores).
• Muscle damage: may reduce markers of post‑exercise muscle damage.

Dosing: how to take creatine

Two valid strategies:

1. No loading: 3–5 g/day, every day. Muscles gradually saturate (~3–4 weeks), then maintain at 3–5 g/day.
2. Loading (optional): 20 g/day for 5–7 days (4 × 5 g), then 3–5 g/day maintenance. Useful to saturate faster.

Weight‑based guide: ~0.03 g/kg/day (e.g., 80 kg → ~2.4 g; in practice 3–5 g/day is simple and effective).

Timing

• Most important: consistent daily intake. Take it every day, ideally at the same time.
• Around training (pre or post) is convenient, but the main effect comes from chronic saturation, not acute timing.
• Taking it with a mixed meal (carbs/protein) may slightly enhance uptake (insulin), but overall impact is modest.

Forms

• Monohydrate: gold‑standard, effective, cheap. Choose micronized powder if your stomach is sensitive.
• HCl, nitrate, ethyl‑ester, buffered: no substantial advantage vs monohydrate, often more expensive.
• Creapure is a German quality label many prefer, but not strictly necessary if your supplier is reputable.

Safety, side effects, myths

Creatine is widely regarded as safe in healthy adults at recommended doses.

Possible side effects:

• GI discomfort (nausea, bloating), especially during loading or single large doses; reduce to 3–5 g, split doses, take with a meal.
• Intracellular water in muscle (≤ 1–2 kg initially) — not fat; often enhances performance and muscle tone.

Common myths:

• “It harms the kidneys”: not supported in healthy individuals. If you have kidney disease or conditions, consult your doctor.
• “It causes cramps/dehydration”: robust data doesn’t support this; if anything, muscle hydration may be better. Stay hydrated.

Cautions:

• Known kidney issues, pregnancy/breastfeeding, minors, or medical treatments: seek medical advice.

Interactions and stacks

• Caffeine: generally compatible. A few isolated studies hint at possible interference on power during loading + high acute caffeine; in practice, moderate co‑use works for most.
• Beta‑alanine: potentially additive for repeated sprints and 1–4 min efforts.
• Protein/carbs: not required but can improve adherence (take with shake/meal).

Who benefits most?

• Beginners/intermediates in resistance training, power athletes, team‑sport athletes.
• Older adults (sarcopenia prevention) with resistance programs.
• Vegetarians/vegans (low baseline stores).

Do you need to cycle creatine?

No. Benefits hinge on saturation. Breaks (e.g., travel) are fine but stores will gradually decline.

Quality, product choice, storage

• Simple monohydrate powder. Minimal ingredients, avoid unnecessary additives.
• Prefer products with third‑party testing (Informed Choice, NSF) to reduce impurity risk.
• Store dry, sealed; avoid humidity (caking).

Quick FAQ

Will I look bloated?

A small early weight increase (intracellular water) is common. It’s not fat and often helps performance and muscle fullness.

Take on rest days?

Yes: every day to maintain saturation.

Empty stomach?

Possible. If sensitive, take with food.

Hot/cold water?

Doesn’t matter. Mix well; micronized powders dissolve better.

Hair loss risk?

One small study suggested increased DHT in rugby players, but evidence is limited and unconfirmed. No solid proof that creatine causes hair loss.

References (selected)

• Meta‑analyses and reviews on creatine performance and safety.
• Cognitive effects and in older or vegetarian populations.
• Example reads:
  • Rawson ES, Venezia AC. Use of creatine in the elderly and evidence for effects on cognitive function in young and old. https://pubmed.ncbi.nlm.nih.gov/
  • Kreider RB, et al. International Society of Sports Nutrition position stand: safety and efficacy of creatine supplementation in exercise, sport, and medicine. https://jissn.biomedcentral.com/
  • Devries MC, Phillips SM. Creatine supplementation and resistance training in older adults. https://pubmed.ncbi.nlm.nih.gov/

This article is educational and not medical advice.